In this context, a recent publication successfully associated AD with gingival inflammation and periodontitis (adjusted OR = 1.69, 95% CI: 1.38 to 2.08 and 1.42, 95% CI: 1.13 to 1.77, respectively) [23], whereas a second study reported that AD influences the gingival crevicular fluid levels of MMP-8 independently of periodontal status [25]. The gene discussed is MMP8; the disease is Alzheimer disease.